In the third "act" of Plato's Gorgias, Callicles "presents himself as a no-holds-barred, bare-knuckled, clear-headed advocate of Realpolitik". Callicles argues the amoralist position that it is natural and just for the strong to dominate the weak and that it is unfair for the weak to resist such oppression by establishing laws to limit the power of the strong. He asserts that institutions and moral codes are established by men who are naturally looking after only their own interests
Callicles begins with a devastating and unforgettable screed against the pursuits of philosophy, and is considered the earliest precursor to the ideas of Friedrich Nietzsche.
We will focus on the Callicles section of the Gorgias. If you've not read this dialogue before you might want to read from the beginning (Socrates' conversations with Gorgias and Polus), but this is not at all necessary.